1. Field of the Invention
The present invention relates to devices and processes for improving the ability of an aircraft occupant to survive a crash of that aircraft. More particularly, the present invention relates to safety oriented apparatus and methods for employing airbags to increase the prospects of survival of an aircraft occupant despite a serious traumatic injury to the aircraft thus occupied. Although potentially applicable to other types of vehicles or crafts, the invention is especially useful for small aircraft, as well as commercial aircraft, and is well suited as a modification of existing aircraft.
2. Description of the Prior Art
The application of airbags as a safety feature to protect a vehicle occupant from injury (or at least minimize the prospect of injury to the vehicle occupant) has received considerable attention in conjunction with the automobile industry. For instance, U.S. Pat. No. 3,836,168 by Nonaka et al shows airbags which are functionally operable in conjunction with a shoulder harness. However, these airbags are intended to position a restraining net, or panel, in response to a collision.
A somewhat accordion-like, deformable instrument panel and a passenger side, upwardly inflating airbag is shown in Oka et al U.S. Pat. No. 3,819,204. The deformable panel extends from the front of the vehicle below and towards the steering wheel of an automobile to absorb energy while avoiding loss of visibility for the driver. It does not address the problem of minimizing injury to a seat occupant without impacting the steering mechanism, as is involved in aircraft accidents.
An airbag configuration intended to expand laterally in front of a bench-type seat in an automobile, and employing a configuration using multiple compartments within a single airbag is shown in U.S. Pat. No. 4,262,931 by Strasser et al. While the intended purpose of this lateral extension is to provide airbag protection for the center occupant of such a bench-type automobile front seat, the patent does not suggest use of a laterally extending airbag so as to cover a side post or offset protection feature, nor does it teach adaptation of such a concept to aircraft.
The prior art has suggested double actuations of airbags, such as in U.S. Pat. Nos. 5,077,744 by Hirabayashi and 4,449,728 by Pilatzki, for example. In Hirabayashi, a unitary airbag is actuated twice in sequence. That is, a first gas generator is initially actuated by Hirabayashi and, at a predetermined time interval later, a second gas generator is actuated. Obviously, the Hirabayashi device could only prove useful in an airplane if the predetermined time interval between actuations happens to exactly coincide with the time interval between the two traumatic events to the aircraft. Hirabayashi does not suggest a system which includes dual (or multiple) collision sensing for the purpose of controlling pressurization of a common airbag, nor of multiple airbags at a common occupant protecting location.
The Pilatzki patent shows two separate airbags, both stowed in the steering column hub. The first airbag is actuated on a collision-sensing level of a first magnitude, whereas a larger second airbag is actuated when an event characterized as a "more violent smash-up" has occurred. Pilatzki does not teach dual airbag actuation based upon sequential traumatic event sensing.
Some prior art has addressed specific applications of airbags to aircraft, such as in U.S. Pat. No. 4,508,294 by Lorch and 3,218,103 by Boyce. The Lorch patent includes a bidirectionally expanding set of airbags from a hoop around the waist of the aircraft occupant to encapsulate that occupant upon actuation. The Boyce patent likewise teaches use of a relatively complete encapsulation of the occupant of a seat although it is shown operational in conjunction with a shoulder harness.
None of the known prior art teaches use of airbags which extend both between the dash and a yoke, or steering column, as well as between that steering column and the occupant so as to neutralize any airbag actuation effect upon the steering column while providing impact absorption functions. Accordingly, it is apparent that an airbag system which is configured so as to neutralize actuation effects upon the yoke, or stick, of an aircraft is not shown or taught in the prior art, nor is the use of double airbag actuation based upon sequential collision event sensings. Further, the prior art devices fail to sense multiple trauma events so as to perform the double actuation, nor do they provide for reliable excessive G-force sensing through redundancy and majority voting.